/* -*- c++ -*- (enables emacs c++ mode) */
/*===========================================================================
 
 Copyright (C) 1995-2012 Yves Renard
 
 This file is a part of GETFEM++
 
 Getfem++  is  free software;  you  can  redistribute  it  and/or modify it
 under  the  terms  of the  GNU  Lesser General Public License as published
 by  the  Free Software Foundation;  either version 3 of the License,  or
 (at your option) any later version along with the GCC Runtime Library
 Exception either version 3.1 or (at your option) any later version.
 This program  is  distributed  in  the  hope  that it will be useful,  but
 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 or  FITNESS  FOR  A PARTICULAR PURPOSE.  See the GNU Lesser General Public
 License and GCC Runtime Library Exception for more details.
 You  should  have received a copy of the GNU Lesser General Public License
 along  with  this program;  if not, write to the Free Software Foundation,
 Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
 
 As a special exception, you  may use  this file  as it is a part of a free
 software  library  without  restriction.  Specifically,  if   other  files
 instantiate  templates  or  use macros or inline functions from this file,
 or  you compile this  file  and  link  it  with other files  to produce an
 executable, this file  does  not  by itself cause the resulting executable
 to be covered  by the GNU Lesser General Public License.  This   exception
 does not  however  invalidate  any  other  reasons why the executable file
 might be covered by the GNU Lesser General Public License.
 
===========================================================================*/

/**@file dal_tas.h
   @author  Yves Renard <Yves.Renard@insa-lyon.fr>
   @date June 01, 1995.
   @brief Heap implementation.
*/
#ifndef DAL_TAS_H__
#define DAL_TAS_H__

#include "dal_basic.h"
#include "dal_bit_vector.h"

namespace dal
{

  template<class T, unsigned char pks = 5> class dynamic_tas;

  template<class T, unsigned char pks = 5> struct dnt_iterator
  {
    typedef T             value_type;
    typedef value_type*   pointer;
    typedef value_type&   reference;
    typedef size_t        size_type;
    typedef ptrdiff_t     difference_type;
    typedef std::bidirectional_iterator_tag iterator_category;
    
    typename dynamic_array<T,pks>::iterator id;
    bit_vector::iterator ib;
    size_type lt;
    
    dnt_iterator(void) {}
    dnt_iterator(dynamic_tas<T,pks> &da, bit_vector &bv, size_type ii)
      : id(da, ii), ib(bv, ii) { lt = da.index().last_true(); }
    
    inline size_type index(void) const { return id.index(); }
    
    dnt_iterator &operator ++();
    dnt_iterator &operator --()
    { while (!*(--ib)) --id; --id; return *this; }
    dnt_iterator operator ++(int)
    {  dnt_iterator tmp = *this; ++(*this); return tmp; }
    dnt_iterator operator --(int)
    { dnt_iterator tmp = *this; --(*this); return tmp; }

    difference_type operator -(const dnt_iterator &i) const
    { return id - i.id; }

	
    reference operator *() const { return (*id); }
    pointer operator->() const { return &(operator*()); }

    bool operator ==(const dnt_iterator &i) const { return i.id==id;}
    bool operator !=(const dnt_iterator &i) const { return i.id!=id;}
    bool operator < (const dnt_iterator &i) const { return id <i.id;}
  };
  
  template<class T, unsigned char pks> dnt_iterator<T, pks> &
  dnt_iterator<T, pks>::operator ++()
  { ++ib; ++id; while(id.in <= lt && !*ib) {++ib; ++id; } return *this; }

  template<class T, unsigned char pks = 5> struct dnt_const_iterator {
    typedef T                   value_type;
    typedef const value_type*   pointer;
    typedef const value_type&   reference;
    typedef size_t              size_type;
    typedef ptrdiff_t           difference_type;
    typedef std::bidirectional_iterator_tag iterator_category;
    
    typename dynamic_array<T,pks>::const_iterator id;
    bit_vector::const_iterator ib;
    size_type lt; 
    
    dnt_const_iterator(void) {}
    dnt_const_iterator(const dynamic_tas<T,pks> &da, size_type ii)
      : id(da, ii), ib(da.index(), ii) { lt = da.index().last_true(); }
    dnt_const_iterator(const dnt_iterator<T,pks> &it)
      : id(it.id), ib(it.ib), lt(it.lt) { }
    
    inline size_type index(void) const { return id.index(); }

    dnt_const_iterator &operator ++()
    { ++ib; ++id; while(id.in <= lt && !*ib) {++ib; ++id; } return *this; }
    dnt_const_iterator &operator --()
    { while (!*(--ib)) --id; --id; return *this; }
    dnt_const_iterator operator ++(int)
    {  dnt_const_iterator tmp = *this; ++(*this); return tmp; }
    dnt_const_iterator operator --(int)
    { dnt_const_iterator tmp = *this; --(*this); return tmp; }

    difference_type operator -(const dnt_const_iterator &i) const
    { return id - i.id; }
	
    reference operator *() const { return (*id); }
    pointer operator->() const { return &(operator*()); }
    
    bool operator ==(const dnt_const_iterator &i) const
    { return i.id == id;}
    bool operator !=(const dnt_const_iterator &i) const
    { return i.id != id;}
    bool operator < (const dnt_const_iterator &i) const
    { return id < i.id;}
  };

  template<class T, unsigned char pks> class dynamic_tas
    : public dynamic_array<T, pks> {
  protected :
    bit_vector ind;
    
  public :
    typedef typename dynamic_array<T, pks>::iterator iterator;
    typedef typename dynamic_array<T, pks>::const_iterator const_iterator;
    typedef dnt_iterator<T, pks> tas_iterator;
    typedef dnt_const_iterator<T, pks> const_tas_iterator;
    typedef typename dynamic_array<T, pks>::size_type size_type;
    
    size_type memsize(void) const
    {	return dynamic_array<T, pks>::memsize() + ind.memsize(); }
    size_type size(void) const
    { return (ind.card() == 0) ? 0 : (ind.last_true() + 1); }
    size_type ind_first(void) const
    { return (ind.card() == 0) ? 0 : ind.first_true(); }
    size_type ind_last(void) const
    { return (ind.card() == 0) ? 0 : ind.last_true(); }
    size_type card(void) const { return ind.card(); }
    
    tas_iterator tas_begin(void)
    { return tas_iterator(*this, ind, ind_first()); }
    const_tas_iterator tas_begin(void) const
    { return const_tas_iterator(*this, ind_first()); }
    tas_iterator tas_end(void) { return tas_iterator(*this, ind, size()); }
    const_tas_iterator tas_end(void) const
    { return const_tas_iterator(*this, size()); }
    
    const bit_vector &index(void) const { return ind; }
    bool index_valid(size_type i) const { return ind[i]; }
    bool empty(void) const { return (ind.card() == 0); }
    
    void swap(size_type i, size_type j);
    void compact(void);
    size_type add(const T &e)
    { size_type n=ind.first_false(); ind[n]=true; (*this)[n]=e;  return n; }
    void add_to_index(size_type i, const T &e) { ind[i]=true; (*this)[i]=e; }
    void sup(size_type n) { ind[n] = false; }
    void clear(void) { dynamic_array<T,pks>::clear(); ind.clear(); }
  };

  template<class T, unsigned char pks>
    void dynamic_tas<T, pks>::swap(size_type i, size_type j) {
    bool ti = ind[i], tj = ind[j]; ind.swap(i,j);
    if (!ti &&  tj) (*this)[i] = (*this)[j];
    if (ti  && !tj) (*this)[j] = (*this)[i];
    if (ti  &&  tj) std::swap((*this)[i], (*this)[j]);
  }

  template<class T, unsigned char pks>
    void dynamic_tas<T, pks>::compact(void) {
    if (!empty())
      while (ind.last_true() >= ind.card())
	swap(ind.first_false(), ind.last_true());
  }
}

#endif /* DAL_TAS_H__ */
